This application is a 35 USC 371 of PCT/KR99/00092, filed Mar. 2, 1999.
This invention relates to an automatic machine to form curved plates of ship""s hull-pieces in shipbuilding process, more particularly, to an automatic machine can form curved plates by heating any one side of the plates locally with heating apparatuses.
In the ship production process, a ship""s hull is fabricated by forming the pieces out of the plates with any thickness in accordance with design data and welding these pieces.
In general, there are two ways to form the curved hull-pieces: hot forming method and cold forming method. Hot forming method of those methods has been used for the completing work of curved plates, the second, or longitudinal forming process of doubly curved plates, and the remove of undesired deformation by welding as it can easily cause residual thermal plastic deformation by heating.
Since plates are heated on along the straight line in the hot forming method, the method is called xe2x80x9cline heating process.xe2x80x9d This work has been manually performed only by some experts. One worker heats the plate toward the given direction with a heating torch and a cooler or one heats the plate with a torch and another cools down the plate along the heated line with a cooler.
Also, in such former work the workers has used templates, the measuring gauges which are previously made of wood in order to make sure how much the plates are formed. If the templates perfectly contact the formed plate at specific locations, they admit that the plate is formed as desired.
So far, as previously mentioned all formation process of the curved plates has been manually performed only by some workers. It means that the formation process has been performed only with experiences of the line-heating experts, not with the information which is derived from the accurate and theoretical backgrounds. That has decreased the productivity in the formation of the curved plates and the fabrication has been made inaccurately. But the formation of the curved plates requires the high accuracy in the shipbuilding process.
In conclusion, such former process for the formation of the ship""s hull-pieces, in which heating, cooling, and measuring is manually performed by some experts has difficulties in precise fabrication and decreases the efficiency of ship production. And there has not been any automatic machine to complete hot forming process of ship""s hull-pieces.
In order to improve such problems, our aim in this invention is to provide an automatic machine for the formation of ship""s curved hull-pieces to enable that process by heating, cooling and measuring plates to be systemized, to be standardized, and to be automated according to the prefabricated information instead of experiences of skillful workers.
Through the automation of such hot forming works, the productivity in the formation of the curved plates and its accuracy can be improved, this invention is about such automatic machine.
To accomplish the previous subjects, this invention has feature that an automatic machine is designed to implement systematic and accurate forming process by equipping the following devices.
Jig table to be equipped with many jigs to support any shaped steel plates and load-constraining apparatus to prevent the undesired deformation by uniformly sharing the load among the edges of the plates
Heating device including a torch to locally heat one side of steel plates up to the required temperature (about 800xc2x0 C.), setting up over a jig table and moving before and behind, and left and right
Cooling device to immediately cool down the heated plates by spraying out coolant from several nozzles, which is set up around a torch and moves along the same path as the torch
Measuring device to measure the formed plates and other information with a gauge to be set up beside the cooling device, and to transmit the data to the control system through A/D converter to convert analogue signals sent by the gauge to digital signals
Driving device to include a transverse guide rail, a longitudinal guide rail, motors, chains, belts, etc., all of which enable the torch, the cooler, and the measuring gauge to move in accordance with commands of a control system
Control device to consist of main controllers and a display device, where main controllers systematically handle the operations of this machine during forming and the operating state and results are monitored through the display device.
According to one aspect of this invention, there is provided an automatic machine for ship""s curved hull-pieces includes jig table to support steel plates; heating device including a torch to heat one side of steel plates up to the required temperature (about 800xc2x0 C.), setting up over a jig table and moving before and behind, and left and right; cooling device to cool down the heated plates by spraying out coolant from several nozzles, which is set up around a torch and moves along the same path as the torch; measuring device to measure the formed plates and other information with a gauge to be set up beside the cooling device, and to transmit the data to the control system through A/D converter to convert analogue signals sent by the gauge to digital signals; driving device to include a transverse guide rail, a longitudinal guide rail, motors, chains, belts, all of which enable the torch, the cooler, and the measuring gauge to move in accordance with commands of a control system; and control device to consist of main controllers and a display device, where main controllers handle the operations of this machine during forming and the operating state and results are monitored through the display device.
According to another aspect of this invention, the heating device can be one of gas-oxygen flaming, laser, electric induction heating, and electronic beam heating.
According to another aspect of this invention, there is provided the automatic machine for ship""s curved hull-pieces having the cooling device whose cooling method is one of water cooling and air cooling.
According to another aspect of this invention, the heating device by the gas flaming consists of gas-supplying tanks, oxygen-supplying tanks, pressure controllers which control the quantity of gas and oxygen, a heating apparatus, or a torch, and an igniter.
According to another aspect of this invention, the jig table consists of the load-constraining device and several jigs to have the function of load-constraining device to uniformly distribute the load at edges of the plate in order to prevent the undesired deformation and the function of jigs to support the bottom of the plates by stretching and shrinking and to be equipped with the contact sensor on its end.